If you click on a download link in Internet Explorer or in another browser, IDM will take over and accelerate this download. In this case you don't need to do anything special, just browse the Internet as you usually do. IDM takes over a download from Internet Explorer if its type matches the list of types/extensions. The list of file types/extensions to download with IDM can be edited in Options->General. If IDM has taken over a download, it shows the following dialog
Download File Info Dialog
If you click on Download Later button, URL (web address) will be added to the list of downloads, but the download process doesn't start. If you click on Start Download button, IDM will start downloading the file immediately. IDM lets you associate your downloads with IDM categories. IDM suggests the category and the default download directory according to file type. You may edit categories, delete and add new categories in the main IDM window. If you want to see the contents of a zip file before downloading, you may click on Preview button.
IDM will take over any download if you hold down the CTRL key while clicking its download link in Internet Explorer. (you should check "Use CTRL key with IE click monitoring" box in "IDM Options->General").
If you hold down the ALT key while clicking on a download link in IE, IDM will not take over the download and let Internet Explorer download the file. (you should check "Use ALT key with IE click monitoring" box in "IDM Options->General")
If you don't want IDM to take over any downloads from a browser, turn off the browser integration in IDM options. After turning off or on the browser integration in "IDM Options->General", don't forget to restart the browser.
Remember if Internet Download Manager had problems downloading file, you should press Alt while clicking on a link to let the browser process the download.